Surge relief



J. TRUMBULL SURGE RELIEF May 29, 1951 Filed March 13, 1946 Patented May 29, 1951 SURGE RELIEF John Trumbull, Chicago, Ill-., ass,ignor' to Robert F. Trumbull & Company, a corporationof Illiv "nois Application March 13, 1946, Serial No 654,093

Claims.

This invention relates to a surge relief, and more particularly to a surge relief for use on gas lines connected with asphalt stills.

In the manufacture of air-blown asphalt it is customary to withdraw the outgoing gases under suction from a battery of stills and introduce them to a manifold which is usually underground. Occasionally the oil being blown becomes too hot, and .as a result there may be an ignition of the outgoing gases which causes a puff or mild explosion. If the flame of this explosion is transmitted to the manifold a larger explosion or series of explosions may occur. The present practice is to provide frangible diaphragms in the gas ducts leading from the stills to the manifold, these diaphragms being blown out by the explosion. The replacement of such diaphragms is a laborious and relatively expensive matter.

The present invention replaces these diaphragms with a surge relief element which in its preferred form comprises a sheet metal plate pivotally mounted at a bend in the gas duct. The plate is so mounted that when it has been opened slightly by a surge of gas, it is automatically opened to full position, completely opening the gas duct communicating with the still. At the same time, another portion of the plate completely closes that portion of the duct communicating with the manifold.

The invention may also be manually operated in the event that an operator believes that a condition likely to lead to puff-back may occur or when it is desirable to cut off the still from the system for any other reason.

The invention is illustrated in the drawings in which Figure 1 is a fragmentary plan view of a portion of a battery of stills; and

Fig. 2 is a sectional elevation along line 2-2 of Fig. 1 showing a portion of the end of a still and gas line illustrating the surge relief element in normal operaton position, and showing in dotted lines the element in an open position.

The invention is shown as applied to a battery of stills I0, each of which is provided with an upwardly directed gas line I I in its upper surface. This line is normally circular in cross-section at its lower portion I2, but it is preferably rectangular in it upper portion I3, the two portions being joined by flanges I 4. The upper end of the gas line is provided with a full opening I5 which is normally closed by one arm I 6 of the plate H.

A second gas line 20, likewise rectangular in form, communicate at right angles with the primary gas line II. It is connected by flanges 2I to the usual circular gas duct 22 which in turn is connected with the manifold 23.

The plate I! is pivotally mounted at I8 near the junction of gas ducts I I and 20. The plate is provided with an inner arm I9 which normally is adjacent the upper wall of the duct 20. A reinforcing frame 25 may be provided. This frame has a horizontal member 26 normally fitting the open end I5 of the duct II and a vertical leg 21 reinforcing the open end of the duct 20. This frame may be braced by reinforcing rods 31.

The plate I! has welded on its upper surface a pin 30 which is journalled in the pivotal mountings I8. This pin is provided at one end with a lever arm 3| to which a heavy spring 32 is attached. The arm also carries a cable 33 for manual operation of the duct.

In the operation of the invention, if gas pressure accumulates within the still it will tend to vent through the duct II, proceeding vertically upward therein until the gas strikes the arm I6 of the plate H. The spring 32 normally holds the plate in closed position. Any severe accumulation of pressure, however, will open the plate and an opening of an inch or two will carry the arm 3! past dead center, after which the spring 32 will draw the plate to its completely open position. In this position, the arm I9 of the plate closes the duct 20 and all gas from the still is not only vented from the atmosphere but the still is placed out of communication with the manifold.

It will be noted that the gas ducts II and 20 are left unobstructed. This is of particular importance in connection with asphalt stills, inasmuch as the gases from such stills carry with them matter which tends to precipitate and build up obstructions in the gas ducts.

When it is desired to operate the surge relief manually, presure may be exerted on the cable 33 to pull the arm 3| over dead center. The device may readily be reset by hand pressure on the plate, or by pushing or pulling thereon with any suitable implement.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom.

I claim:

1. Apparatus comprising a primary gas relief line having an open end, a secondary gas relief line angularly communicating with the primary line near the open end thereof, a surge relief element at the junction of the primary and secondary gas lines, said element comprising a plate pivotally mounted near the end of the primary line, a portion of said plate closing the open end of the primary gas line, and a second portion of the plate being adapted to close the communication between the primary and secondary lines when the first portion of the plate is moved into open position, means for normally holding the plate in position to close the primary line, and automatic means for moving the plate to a position closing the communication between the primary and secondary ducts when the plate has been moved a predetermined distance.

2. Apparatus as set forth in claim 1 in which the gas lines are rectangular in cross-section.

3. Apparatus as set forth in claim 1 in which the plate is pivotally mounted substantially along a line dividing it into two equal portions.

4. Apparatus as set forth in claim 1 in which there is provided a gas manifold and the sec- 4 ondary gas line communicates with the gas received in the manifold.

5. Apparatus as set forth in claim 1 in which there is provided as gas manifold and the secondary gas line communicates with the gas received in the manifold from a battery of asphalt blowing stills.

JOHN TRUMBULL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

